Skip fold placeholders when moving right

This relies on a new `eagerWrap` option to clipScreenPosition which
will wrap positions inside of atomic line fragments (which is what fold
placeholders are) to the end of the fragment rather than the beginning.
It also wraps positions beyond the end of a hard line to the next line,
which means Cursor.moveRight just has to increment the column, then
call clipPosition with eager wrap set to true to get all the correct
behavior.

spec/atom/line-folder-spec.coffee

@@ -313,7 +313,7 @@ describe "LineFolder", ->
         expect(folder.bufferPositionForScreenPosition([4, 13])).toEqual [4, 15]
         expect(folder.bufferPositionForScreenPosition([4, 18])).toEqual [4, 20]
 
-  describe ".clipScreenPosition(screenPosition)", ->
+  describe ".clipScreenPosition(screenPosition, eagerWrap=false)", ->
     beforeEach ->
       folder.createFold(new Range([4, 29], [7, 4]))
 
@@ -326,10 +326,18 @@ describe "LineFolder", ->
       expect(folder.clipScreenPosition([4, 1000])).toEqual [4, 33]
       expect(folder.clipScreenPosition([1000, 1000])).toEqual [9, 2]
 
-    it "clips positions inside a placeholder to the beginning of the placeholder", ->
-      expect(folder.clipScreenPosition([4, 30])).toEqual [4, 29]
-      # expect(folder.clipScreenPosition([4, 31])).toEqual [4, 29]
-      # expect(folder.clipScreenPosition([4, 32])).toEqual [4, 32]
+    describe "when eagerWrap is false (the default)", ->
+      it "clips positions inside a placeholder to the beginning of the placeholder", ->
+        expect(folder.clipScreenPosition([4, 30])).toEqual [4, 29]
+        expect(folder.clipScreenPosition([4, 31])).toEqual [4, 29]
+        expect(folder.clipScreenPosition([4, 32])).toEqual [4, 32]
+
+    describe "when eagerWrap is true", ->
+      it "clips positions inside a placeholder to the end of the placeholder", ->
+        expect(folder.clipScreenPosition([4, 29], true)).toEqual [4, 29]
+        expect(folder.clipScreenPosition([4, 30], true)).toEqual [4, 32]
+        expect(folder.clipScreenPosition([4, 31], true)).toEqual [4, 32]
+        expect(folder.clipScreenPosition([4, 32], true)).toEqual [4, 32]
 
 
 

spec/atom/line-wrapper-spec.coffee

@@ -237,21 +237,45 @@ describe "LineWrapper", ->
           expect(line2.endColumn).toBe 14
           expect(line2.text.length).toBe 3
 
-  describe ".clipScreenPosition(screenPosition)", ->
-    it "returns the nearest valid position based on the current screen lines", ->
-      expect(wrapper.clipScreenPosition([-1, -1])).toEqual [0, 0]
-      expect(wrapper.clipScreenPosition([0, -1])).toEqual [0, 0]
-      expect(wrapper.clipScreenPosition([1, 10000])).toEqual [1, 30]
-      expect(wrapper.clipScreenPosition([3, 51])).toEqual [4, 0]
-      expect(wrapper.clipScreenPosition([3, 58])).toEqual [4, 0]
+  describe ".clipScreenPosition(screenPosition, eagerWrap=false)", ->
+    it "allows valid positions", ->
       expect(wrapper.clipScreenPosition([4, 5])).toEqual [4, 5]
       expect(wrapper.clipScreenPosition([4, 11])).toEqual [4, 11]
-      expect(wrapper.clipScreenPosition([4, 30])).toEqual [4, 11]
-      expect(wrapper.clipScreenPosition([4, 1000])).toEqual [4, 11]
+
+    it "disallows negative positions", ->
+      expect(wrapper.clipScreenPosition([-1, -1])).toEqual [0, 0]
+      expect(wrapper.clipScreenPosition([0, -1])).toEqual [0, 0]
+
+    it "disallows positions beyond the last row", ->
+      expect(wrapper.clipScreenPosition([1000, 0])).toEqual [15, 2]
       expect(wrapper.clipScreenPosition([1000, 1000])).toEqual [15, 2]
 
-    it "also clips the screen position with respect to fold placeholders", ->
-      folder.createFold(new Range([3, 55], [3, 59]))
-      expect(wrapper.clipScreenPosition([4, 5])).toEqual [4, 4]
-      expect(wrapper.clipScreenPosition([4, 6])).toEqual [4, 4]
-      
+    it "wraps positions at the end of soft-wrapped lines to the next screen line", ->
+      expect(wrapper.clipScreenPosition([3, 51])).toEqual [4, 0]
+      expect(wrapper.clipScreenPosition([3, 58])).toEqual [4, 0]
+      expect(wrapper.clipScreenPosition([3, 1000])).toEqual [4, 0]
+
+    describe "when eagerWrap is false (the default)", ->
+      it "wraps positions beyond the end of hard lines to the end of the line", ->
+        expect(wrapper.clipScreenPosition([1, 10000])).toEqual [1, 30]
+        expect(wrapper.clipScreenPosition([4, 30])).toEqual [4, 11]
+        expect(wrapper.clipScreenPosition([4, 1000])).toEqual [4, 11]
+
+      it "clips screen positions in the middle of fold placeholders to the to the beginning of fold placeholders", ->
+        folder.createFold(new Range([3, 55], [3, 59]))
+        expect(wrapper.clipScreenPosition([4, 5])).toEqual [4, 4]
+        expect(wrapper.clipScreenPosition([4, 6])).toEqual [4, 4]
+        expect(wrapper.clipScreenPosition([4, 7])).toEqual [4, 7]
+
+    describe "when eagerWrap is true", ->
+      it "wraps positions past the end of non-softwrapped lines to the next line", ->
+        expect(wrapper.clipScreenPosition([0, 29], true)).toEqual [0, 29]
+        expect(wrapper.clipScreenPosition([0, 30], true)).toEqual [1, 0]
+        expect(wrapper.clipScreenPosition([0, 1000], true)).toEqual [1, 0]
+
+      it "wraps the screen positions in the middle of fold placeholders to the end of the placeholder", ->
+        folder.createFold(new Range([3, 55], [3, 59]))
+        expect(wrapper.clipScreenPosition([4, 4], true)).toEqual [4, 4]
+        expect(wrapper.clipScreenPosition([4, 5], true)).toEqual [4, 7]
+        expect(wrapper.clipScreenPosition([4, 6], true)).toEqual [4, 7]
+

src/atom/cursor.coffee

@@ -77,12 +77,7 @@ class Cursor extends View
 
   moveRight: ->
     { row, column } = @getScreenPosition()
-    if column < @editor.buffer.getLine(row).length
-      column++
-    else if row < @editor.buffer.numLines() - 1
-      row++
-      column = 0
-    @setScreenPosition({row, column})
+    @setScreenPosition(@editor.clipScreenPosition([row, column + 1], true))
 
   moveLeft: ->
     { row, column } = @getScreenPosition()

src/atom/editor.coffee

@@ -211,8 +211,8 @@ class Editor extends View
     else
       $(window).off 'resize', @_setMaxLineLength
 
-  clipScreenPosition: (screenPosition) ->
-    @lineWrapper.clipScreenPosition(screenPosition)
+  clipScreenPosition: (screenPosition, eagerWrap=false) ->
+    @lineWrapper.clipScreenPosition(screenPosition, eagerWrap)
 
   pixelPositionForScreenPosition: ({row, column}) ->
     { top: row * @lineHeight, left: column * @charWidth }

src/atom/line-folder.coffee

@@ -134,8 +134,8 @@ class LineFolder
   bufferPositionForScreenPosition: (screenPosition) ->
     @lineMap.bufferPositionForScreenPosition(screenPosition)
 
-  clipScreenPosition: (screenPosition) ->
-    @lineMap.clipScreenPosition(screenPosition)
+  clipScreenPosition: (screenPosition, eagerWrap=false) ->
+    @lineMap.clipScreenPosition(screenPosition, eagerWrap)
 
   screenRangeForBufferRange: (bufferRange) ->
     @lineMap.screenRangeForBufferRange(bufferRange)

src/atom/line-map.coffee

@@ -141,10 +141,9 @@ class LineMap
     end = @bufferPositionForScreenPosition(screenRange.end)
     new Range(start, end)
 
-  clipScreenPosition: (screenPosition) ->
+  clipScreenPosition: (screenPosition, eagerWrap) ->
     screenPosition = Point.fromObject(screenPosition)
 
-    debugger if screenPosition.isEqual [7,4]
     screenPosition = new Point(Math.max(0, screenPosition.row), Math.max(0, screenPosition.column))
     maxRow = @lastScreenRow()
     if screenPosition.row > maxRow
@@ -157,8 +156,17 @@ class LineMap
       break if nextDelta.isGreaterThan(screenPosition)
       screenDelta = nextDelta
 
-    maxColumn = screenDelta.column + screenLine.lengthForClipping()
-    screenDelta.column = Math.min(maxColumn, screenPosition.column)
+    if screenLine.isAtomic
+      if eagerWrap and screenPosition.column > screenDelta.column
+        screenDelta.column = screenDelta.column + screenLine.text.length
+    else
+      maxColumn = screenDelta.column + screenLine.text.length
+      if eagerWrap and screenPosition.column > maxColumn
+        screenDelta.row++
+        screenDelta.column = 0
+      else
+        screenDelta.column = Math.min(maxColumn, screenPosition.column)
+
     screenDelta
 
   logLines: (start=0, end=@screenLineCount() - 1)->

src/atom/line-wrapper.coffee

@@ -93,11 +93,15 @@ class LineWrapper
     @lineFolder.bufferRangeForScreenRange(
       @lineMap.bufferRangeForScreenRange(screenRange))
 
-  clipScreenPosition: (screenPosition) ->
+  clipScreenPosition: (screenPosition, eagerWrap=false) ->
     @lineMap.screenPositionForBufferPosition(
       @lineFolder.clipScreenPosition(
         @lineMap.bufferPositionForScreenPosition(
-          @lineMap.clipScreenPosition(screenPosition))))
+          @lineMap.clipScreenPosition(screenPosition, eagerWrap)
+        ),
+        eagerWrap
+      )
+    )
 
   lineForScreenRow: (screenRow) ->
     @linesForScreenRows(screenRow, screenRow)[0]